1. Field of the Invention
The present invention relates to an image forming apparatus, a printing job carrying out method and a computer readable information recording medium that stores a program for carrying out, by the image forming apparatus, printing jobs previously stored in a server or a storing part of the image forming apparatus.
2. Description of the Related Art
An image forming apparatus is known which does not immediately print printing data received from a host computer, spools (i.e., stores) the printing data in a printing server or the image forming apparatus, and prints printing data selected from a list of the spooled printing data after a user logs in.
In such a printing system including the printing server, the user first inputs a printing instruction to a client PC (Personal Computer). The client PC transmits printing jobs corresponding to the input printing instruction to the printing server or the image forming apparatus. The printing server does not immediately transfer the printing jobs to the image forming apparatus, or the image forming apparatus does not immediately carry out the printing jobs, and stores the printing jobs in a storage such as a HDD (Hard Disk Drive). After that, the user operates the image forming apparatus, and inputs an instruction to carry out the stored printing jobs. The image forming apparatus obtains the printing jobs from the HDD or the printing server in response to the input instruction, and carries out the printing jobs (for example, see Japanese Laid-Open Patent Application No. 2007-200284 (Patent Document 1)).
In such a printing system, it is not preferable from a security viewpoint that another user carries out the printing jobs that have been stored by one user. Therefore, a process of authenticating a user may be carried out when the printing jobs are to be carried out in the image forming apparatus. For example, a user inputs his or her own authentication information when inputting an instruction to carry out the stored printing jobs. Then, in a case where authentication has succeeded based on the authentication information, carrying out of the printing jobs concerning the user is permitted. The user is thus allowed to store the printing jobs in the printing server without being aware of the specific image forming apparatus to be actually used.
Thus, the user can print only his or her own printing data, and therefore, it is possible to prevent his or her own printed papers from being taken by another user, or important printed papers from being read by another user.
However, there may be a case where, after the user logs in, and while the user is logged in, the user goes away from the image forming apparatus for greeting guests, for example. In a case where the user has used an IC (Integrated Circuit) card for the logging in, the user may hold the IC card and go away from the image forming apparatus for greeting guests. However, a logged out state does not occur just because the IC card is removed. Therefore, in order to prevent another person from carrying out the printing jobs, a predetermined operation has to be carried out. That is, for example, the printing has to be manually cancelled (stopped) and an operation of logging out has to be carried out. Therefore, the user may feel the operation of logging out as being troublesome, or may forget the operation of logging out. If so, another person may read the printed papers.